A number of molecular biological methods involve the detection of nucleotide sequences, or the tagging of nucleotide sequences with reporter groups. For example, the widely utilised polymerase chain reaction technique (PCR) allows many copies of a desired DNA to be generated from only a few target molecules within a period of 1 to 2 hours and consequently has found applications of nucleic acid detection techniques previously limited by low sensitivity. Detection of amplified PCR products may be carried out in a number of ways. It is most desirable to be able to detect amplification products non-radioactively, for example, using a reporter group within the amplified nucleotide sequences.
Similarly, in reactions such as nick translation, it is desirable to incorporate a labelled nucleotide into reaction products produced by DNA polymerase or RNA polymerase for subsequent detection of hybridisation products.